jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp@d1605aabd0a1 (annotated)

src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp@d1605aabd0a1 (annotated)

src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp

Wed, 02 Jul 2008 12:55:16 -0700

author: xdono
date: Wed, 02 Jul 2008 12:55:16 -0700
changeset 631: d1605aabd0a1
parent 548: ba764ed4b6f2
child 916: 7d7a7c599c17
permissions: -rw-r--r--

6719955: Update copyright year
Summary: Update copyright year for files that have been modified in 2008
Reviewed-by: ohair, tbell

 /*
  * Copyright 2002-2008 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 #include "incls/_precompiled.incl"
 #include "incls/_psPromotionManager.cpp.incl"
 PSPromotionManager**         PSPromotionManager::_manager_array = NULL;
 OopStarTaskQueueSet*         PSPromotionManager::_stack_array_depth = NULL;
 OopTaskQueueSet*             PSPromotionManager::_stack_array_breadth = NULL;
 PSOldGen*                    PSPromotionManager::_old_gen = NULL;
 MutableSpace*                PSPromotionManager::_young_space = NULL;
 void PSPromotionManager::initialize() {
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   _old_gen = heap->old_gen();
   _young_space = heap->young_gen()->to_space();
   assert(_manager_array == NULL, "Attempt to initialize twice");
   _manager_array = NEW_C_HEAP_ARRAY(PSPromotionManager*, ParallelGCThreads+1 );
   guarantee(_manager_array != NULL, "Could not initialize promotion manager");
   if (UseDepthFirstScavengeOrder) {
     _stack_array_depth = new OopStarTaskQueueSet(ParallelGCThreads);
     guarantee(_stack_array_depth != NULL, "Count not initialize promotion manager");
   } else {
     _stack_array_breadth = new OopTaskQueueSet(ParallelGCThreads);
     guarantee(_stack_array_breadth != NULL, "Count not initialize promotion manager");
   }
   // Create and register the PSPromotionManager(s) for the worker threads.
   for(uint i=0; i<ParallelGCThreads; i++) {
     _manager_array[i] = new PSPromotionManager();
     guarantee(_manager_array[i] != NULL, "Could not create PSPromotionManager");
     if (UseDepthFirstScavengeOrder) {
       stack_array_depth()->register_queue(i, _manager_array[i]->claimed_stack_depth());
     } else {
       stack_array_breadth()->register_queue(i, _manager_array[i]->claimed_stack_breadth());
     }
   }
   // The VMThread gets its own PSPromotionManager, which is not available
   // for work stealing.
   _manager_array[ParallelGCThreads] = new PSPromotionManager();
   guarantee(_manager_array[ParallelGCThreads] != NULL, "Could not create PSPromotionManager");
 }
 PSPromotionManager* PSPromotionManager::gc_thread_promotion_manager(int index) {
   assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
   assert(_manager_array != NULL, "Sanity");
   return _manager_array[index];
 }
 PSPromotionManager* PSPromotionManager::vm_thread_promotion_manager() {
   assert(_manager_array != NULL, "Sanity");
   return _manager_array[ParallelGCThreads];
 }
 void PSPromotionManager::pre_scavenge() {
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   _young_space = heap->young_gen()->to_space();
   for(uint i=0; i<ParallelGCThreads+1; i++) {
     manager_array(i)->reset();
   }
 }
 void PSPromotionManager::post_scavenge() {
 #if PS_PM_STATS
   print_stats();
 #endif // PS_PM_STATS
   for(uint i=0; i<ParallelGCThreads+1; i++) {
     PSPromotionManager* manager = manager_array(i);
     // the guarantees are a bit gratuitous but, if one fires, we'll
     // have a better idea of what went wrong
     if (i < ParallelGCThreads) {
       guarantee((!UseDepthFirstScavengeOrder ||
                  manager->overflow_stack_depth()->length() <= 0),
                 "promotion manager overflow stack must be empty");
       guarantee((UseDepthFirstScavengeOrder ||
                  manager->overflow_stack_breadth()->length() <= 0),
                 "promotion manager overflow stack must be empty");
       guarantee((!UseDepthFirstScavengeOrder ||
                  manager->claimed_stack_depth()->size() <= 0),
                 "promotion manager claimed stack must be empty");
       guarantee((UseDepthFirstScavengeOrder ||
                  manager->claimed_stack_breadth()->size() <= 0),
                 "promotion manager claimed stack must be empty");
     } else {
       guarantee((!UseDepthFirstScavengeOrder ||
                  manager->overflow_stack_depth()->length() <= 0),
                 "VM Thread promotion manager overflow stack "
                 "must be empty");
       guarantee((UseDepthFirstScavengeOrder ||
                  manager->overflow_stack_breadth()->length() <= 0),
                 "VM Thread promotion manager overflow stack "
                 "must be empty");
       guarantee((!UseDepthFirstScavengeOrder ||
                  manager->claimed_stack_depth()->size() <= 0),
                 "VM Thread promotion manager claimed stack "
                 "must be empty");
       guarantee((UseDepthFirstScavengeOrder ||
                  manager->claimed_stack_breadth()->size() <= 0),
                 "VM Thread promotion manager claimed stack "
                 "must be empty");
     }
     manager->flush_labs();
   }
 }
 #if PS_PM_STATS
 void
 PSPromotionManager::print_stats(uint i) {
   tty->print_cr("---- GC Worker %2d Stats", i);
   tty->print_cr("    total pushes            %8d", _total_pushes);
   tty->print_cr("    masked pushes           %8d", _masked_pushes);
   tty->print_cr("    overflow pushes         %8d", _overflow_pushes);
   tty->print_cr("    max overflow length     %8d", _max_overflow_length);
   tty->print_cr("");
   tty->print_cr("    arrays chunked          %8d", _arrays_chunked);
   tty->print_cr("    array chunks processed  %8d", _array_chunks_processed);
   tty->print_cr("");
   tty->print_cr("    total steals            %8d", _total_steals);
   tty->print_cr("    masked steals           %8d", _masked_steals);
   tty->print_cr("");
 }
 void
 PSPromotionManager::print_stats() {
   tty->print_cr("== GC Tasks Stats (%s), GC %3d",
                 (UseDepthFirstScavengeOrder) ? "Depth-First" : "Breadth-First",
                 Universe::heap()->total_collections());
   for (uint i = 0; i < ParallelGCThreads+1; ++i) {
     PSPromotionManager* manager = manager_array(i);
     manager->print_stats(i);
   }
 }
 #endif // PS_PM_STATS
 PSPromotionManager::PSPromotionManager() {
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   _depth_first = UseDepthFirstScavengeOrder;
   // We set the old lab's start array.
   _old_lab.set_start_array(old_gen()->start_array());
   uint queue_size;
   if (depth_first()) {
     claimed_stack_depth()->initialize();
     queue_size = claimed_stack_depth()->max_elems();
     // We want the overflow stack to be permanent
     _overflow_stack_depth = new (ResourceObj::C_HEAP) GrowableArray<StarTask>(10, true);
     _overflow_stack_breadth = NULL;
   } else {
     claimed_stack_breadth()->initialize();
     queue_size = claimed_stack_breadth()->max_elems();
     // We want the overflow stack to be permanent
     _overflow_stack_breadth = new (ResourceObj::C_HEAP) GrowableArray<oop>(10, true);
     _overflow_stack_depth = NULL;
   }
   _totally_drain = (ParallelGCThreads == 1) || (GCDrainStackTargetSize == 0);
   if (_totally_drain) {
     _target_stack_size = 0;
   } else {
     // don't let the target stack size to be more than 1/4 of the entries
     _target_stack_size = (uint) MIN2((uint) GCDrainStackTargetSize,
                                      (uint) (queue_size / 4));
   }
   _array_chunk_size = ParGCArrayScanChunk;
   // let's choose 1.5x the chunk size
   _min_array_size_for_chunking = 3 * _array_chunk_size / 2;
   reset();
 }
 void PSPromotionManager::reset() {
   assert(claimed_stack_empty(), "reset of non-empty claimed stack");
   assert(overflow_stack_empty(), "reset of non-empty overflow stack");
   // We need to get an assert in here to make sure the labs are always flushed.
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   // Do not prefill the LAB's, save heap wastage!
   HeapWord* lab_base = young_space()->top();
   _young_lab.initialize(MemRegion(lab_base, (size_t)0));
   _young_gen_is_full = false;
   lab_base = old_gen()->object_space()->top();
   _old_lab.initialize(MemRegion(lab_base, (size_t)0));
   _old_gen_is_full = false;
   _prefetch_queue.clear();
 #if PS_PM_STATS
   _total_pushes = 0;
   _masked_pushes = 0;
   _overflow_pushes = 0;
   _max_overflow_length = 0;
   _arrays_chunked = 0;
   _array_chunks_processed = 0;
   _total_steals = 0;
   _masked_steals = 0;
 #endif // PS_PM_STATS
 }
 void PSPromotionManager::drain_stacks_depth(bool totally_drain) {
   assert(depth_first(), "invariant");
   assert(overflow_stack_depth() != NULL, "invariant");
   totally_drain = totally_drain || _totally_drain;
 #ifdef ASSERT
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   MutableSpace* to_space = heap->young_gen()->to_space();
   MutableSpace* old_space = heap->old_gen()->object_space();
   MutableSpace* perm_space = heap->perm_gen()->object_space();
 #endif /* ASSERT */
   do {
     StarTask p;
     // Drain overflow stack first, so other threads can steal from
     // claimed stack while we work.
     while(!overflow_stack_depth()->is_empty()) {
       // linux compiler wants different overloaded operator= in taskqueue to
       // assign to p that the other compilers don't like.
       StarTask ptr = overflow_stack_depth()->pop();
       process_popped_location_depth(ptr);
     }
     if (totally_drain) {
       while (claimed_stack_depth()->pop_local(p)) {
         process_popped_location_depth(p);
       }
     } else {
       while (claimed_stack_depth()->size() > _target_stack_size &&
              claimed_stack_depth()->pop_local(p)) {
         process_popped_location_depth(p);
       }
     }
   } while( (totally_drain && claimed_stack_depth()->size() > 0) ||
            (overflow_stack_depth()->length() > 0) );
   assert(!totally_drain || claimed_stack_empty(), "Sanity");
   assert(totally_drain ||
          claimed_stack_depth()->size() <= _target_stack_size,
          "Sanity");
   assert(overflow_stack_empty(), "Sanity");
 }
 void PSPromotionManager::drain_stacks_breadth(bool totally_drain) {
   assert(!depth_first(), "invariant");
   assert(overflow_stack_breadth() != NULL, "invariant");
   totally_drain = totally_drain || _totally_drain;
 #ifdef ASSERT
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
   MutableSpace* to_space = heap->young_gen()->to_space();
   MutableSpace* old_space = heap->old_gen()->object_space();
   MutableSpace* perm_space = heap->perm_gen()->object_space();
 #endif /* ASSERT */
   do {
     oop obj;
     // Drain overflow stack first, so other threads can steal from
     // claimed stack while we work.
     while(!overflow_stack_breadth()->is_empty()) {
       obj = overflow_stack_breadth()->pop();
       obj->copy_contents(this);
     }
     if (totally_drain) {
       // obj is a reference!!!
       while (claimed_stack_breadth()->pop_local(obj)) {
         // It would be nice to assert about the type of objects we might
         // pop, but they can come from anywhere, unfortunately.
         obj->copy_contents(this);
       }
     } else {
       // obj is a reference!!!
       while (claimed_stack_breadth()->size() > _target_stack_size &&
              claimed_stack_breadth()->pop_local(obj)) {
         // It would be nice to assert about the type of objects we might
         // pop, but they can come from anywhere, unfortunately.
         obj->copy_contents(this);
       }
     }
     // If we could not find any other work, flush the prefetch queue
     if (claimed_stack_breadth()->size() == 0 &&
         (overflow_stack_breadth()->length() == 0)) {
       flush_prefetch_queue();
     }
   } while((totally_drain && claimed_stack_breadth()->size() > 0) ||
           (overflow_stack_breadth()->length() > 0));
   assert(!totally_drain || claimed_stack_empty(), "Sanity");
   assert(totally_drain ||
          claimed_stack_breadth()->size() <= _target_stack_size,
          "Sanity");
   assert(overflow_stack_empty(), "Sanity");
 }
 void PSPromotionManager::flush_labs() {
   assert(claimed_stack_empty(), "Attempt to flush lab with live stack");
   assert(overflow_stack_empty(), "Attempt to flush lab with live overflow stack");
   // If either promotion lab fills up, we can flush the
   // lab but not refill it, so check first.
   assert(!_young_lab.is_flushed() || _young_gen_is_full, "Sanity");
   if (!_young_lab.is_flushed())
     _young_lab.flush();
   assert(!_old_lab.is_flushed() || _old_gen_is_full, "Sanity");
   if (!_old_lab.is_flushed())
     _old_lab.flush();
   // Let PSScavenge know if we overflowed
   if (_young_gen_is_full) {
     PSScavenge::set_survivor_overflow(true);
   }
 }
 //
 // This method is pretty bulky. It would be nice to split it up
 // into smaller submethods, but we need to be careful not to hurt
 // performance.
 //
 oop PSPromotionManager::copy_to_survivor_space(oop o, bool depth_first) {
   assert(PSScavenge::should_scavenge(&o), "Sanity");
   oop new_obj = NULL;
   // NOTE! We must be very careful with any methods that access the mark
   // in o. There may be multiple threads racing on it, and it may be forwarded
   // at any time. Do not use oop methods for accessing the mark!
   markOop test_mark = o->mark();
   // The same test as "o->is_forwarded()"
   if (!test_mark->is_marked()) {
     bool new_obj_is_tenured = false;
     size_t new_obj_size = o->size();
     // Find the objects age, MT safe.
     int age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?
       test_mark->displaced_mark_helper()->age() : test_mark->age();
     // Try allocating obj in to-space (unless too old)
     if (age < PSScavenge::tenuring_threshold()) {
       new_obj = (oop) _young_lab.allocate(new_obj_size);
       if (new_obj == NULL && !_young_gen_is_full) {
         // Do we allocate directly, or flush and refill?
         if (new_obj_size > (YoungPLABSize / 2)) {
           // Allocate this object directly
           new_obj = (oop)young_space()->cas_allocate(new_obj_size);
         } else {
           // Flush and fill
           _young_lab.flush();
           HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);
           if (lab_base != NULL) {
             _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));
             // Try the young lab allocation again.
             new_obj = (oop) _young_lab.allocate(new_obj_size);
           } else {
             _young_gen_is_full = true;
           }
         }
       }
     }
     // Otherwise try allocating obj tenured
     if (new_obj == NULL) {
 #ifndef PRODUCT
       if (Universe::heap()->promotion_should_fail()) {
         return oop_promotion_failed(o, test_mark);
       }
 #endif  // #ifndef PRODUCT
       new_obj = (oop) _old_lab.allocate(new_obj_size);
       new_obj_is_tenured = true;
       if (new_obj == NULL) {
         if (!_old_gen_is_full) {
           // Do we allocate directly, or flush and refill?
           if (new_obj_size > (OldPLABSize / 2)) {
             // Allocate this object directly
             new_obj = (oop)old_gen()->cas_allocate(new_obj_size);
           } else {
             // Flush and fill
             _old_lab.flush();
             HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);
             if(lab_base != NULL) {
               _old_lab.initialize(MemRegion(lab_base, OldPLABSize));
               // Try the old lab allocation again.
               new_obj = (oop) _old_lab.allocate(new_obj_size);
             }
           }
         }
         // This is the promotion failed test, and code handling.
         // The code belongs here for two reasons. It is slightly
         // different thatn the code below, and cannot share the
         // CAS testing code. Keeping the code here also minimizes
         // the impact on the common case fast path code.
         if (new_obj == NULL) {
           _old_gen_is_full = true;
           return oop_promotion_failed(o, test_mark);
         }
       }
     }
     assert(new_obj != NULL, "allocation should have succeeded");
     // Copy obj
     Copy::aligned_disjoint_words((HeapWord*)o, (HeapWord*)new_obj, new_obj_size);
     // Now we have to CAS in the header.
     if (o->cas_forward_to(new_obj, test_mark)) {
       // We won any races, we "own" this object.
       assert(new_obj == o->forwardee(), "Sanity");
       // Increment age if obj still in new generation. Now that
       // we're dealing with a markOop that cannot change, it is
       // okay to use the non mt safe oop methods.
       if (!new_obj_is_tenured) {
         new_obj->incr_age();
         assert(young_space()->contains(new_obj), "Attempt to push non-promoted obj");
       }
       if (depth_first) {
         // Do the size comparison first with new_obj_size, which we
         // already have. Hopefully, only a few objects are larger than
         // _min_array_size_for_chunking, and most of them will be arrays.
         // So, the is->objArray() test would be very infrequent.
         if (new_obj_size > _min_array_size_for_chunking &&
             new_obj->is_objArray() &&
             PSChunkLargeArrays) {
           // we'll chunk it
 #if PS_PM_STATS
           ++_arrays_chunked;
 #endif // PS_PM_STATS
           oop* const masked_o = mask_chunked_array_oop(o);
           push_depth(masked_o);
 #if PS_PM_STATS
           ++_masked_pushes;
 #endif // PS_PM_STATS
         } else {
           // we'll just push its contents
           new_obj->push_contents(this);
         }
       } else {
         push_breadth(new_obj);
       }
     }  else {
       // We lost, someone else "owns" this object
       guarantee(o->is_forwarded(), "Object must be forwarded if the cas failed.");
       // Unallocate the space used. NOTE! We may have directly allocated
       // the object. If so, we cannot deallocate it, so we have to test!
       if (new_obj_is_tenured) {
         if (!_old_lab.unallocate_object(new_obj)) {
           // The promotion lab failed to unallocate the object.
           // We need to overwrite the object with a filler that
           // contains no interior pointers.
           MemRegion mr((HeapWord*)new_obj, new_obj_size);
           // Clean this up and move to oopFactory (see bug 4718422)
           SharedHeap::fill_region_with_object(mr);
         }
       } else {
         if (!_young_lab.unallocate_object(new_obj)) {
           // The promotion lab failed to unallocate the object.
           // We need to overwrite the object with a filler that
           // contains no interior pointers.
           MemRegion mr((HeapWord*)new_obj, new_obj_size);
           // Clean this up and move to oopFactory (see bug 4718422)
           SharedHeap::fill_region_with_object(mr);
         }
       }
       // don't update this before the unallocation!
       new_obj = o->forwardee();
     }
   } else {
     assert(o->is_forwarded(), "Sanity");
     new_obj = o->forwardee();
   }
 #ifdef DEBUG
   // This code must come after the CAS test, or it will print incorrect
   // information.
   if (TraceScavenge) {
     gclog_or_tty->print_cr("{%s %s " PTR_FORMAT " -> " PTR_FORMAT " (" SIZE_FORMAT ")}",
        PSScavenge::should_scavenge(&new_obj) ? "copying" : "tenuring",
        new_obj->blueprint()->internal_name(), o, new_obj, new_obj->size());
   }
 #endif
   return new_obj;
 }
 template <class T> void PSPromotionManager::process_array_chunk_work(
                                                  oop obj,
                                                  int start, int end) {
   assert(start < end, "invariant");
   T* const base      = (T*)objArrayOop(obj)->base();
   T* p               = base + start;
   T* const chunk_end = base + end;
   while (p < chunk_end) {
     if (PSScavenge::should_scavenge(p)) {
       claim_or_forward_depth(p);
     }
     ++p;
   }
 }
 void PSPromotionManager::process_array_chunk(oop old) {
   assert(PSChunkLargeArrays, "invariant");
   assert(old->is_objArray(), "invariant");
   assert(old->is_forwarded(), "invariant");
 #if PS_PM_STATS
   ++_array_chunks_processed;
 #endif // PS_PM_STATS
   oop const obj = old->forwardee();
   int start;
   int const end = arrayOop(old)->length();
   if (end > (int) _min_array_size_for_chunking) {
     // we'll chunk more
     start = end - _array_chunk_size;
     assert(start > 0, "invariant");
     arrayOop(old)->set_length(start);
     push_depth(mask_chunked_array_oop(old));
 #if PS_PM_STATS
     ++_masked_pushes;
 #endif // PS_PM_STATS
   } else {
     // this is the final chunk for this array
     start = 0;
     int const actual_length = arrayOop(obj)->length();
     arrayOop(old)->set_length(actual_length);
   }
   if (UseCompressedOops) {
     process_array_chunk_work<narrowOop>(obj, start, end);
   } else {
     process_array_chunk_work<oop>(obj, start, end);
   }
 }
 oop PSPromotionManager::oop_promotion_failed(oop obj, markOop obj_mark) {
   assert(_old_gen_is_full || PromotionFailureALot, "Sanity");
   // Attempt to CAS in the header.
   // This tests if the header is still the same as when
   // this started.  If it is the same (i.e., no forwarding
   // pointer has been installed), then this thread owns
   // it.
   if (obj->cas_forward_to(obj, obj_mark)) {
     // We won any races, we "own" this object.
     assert(obj == obj->forwardee(), "Sanity");
     if (depth_first()) {
       obj->push_contents(this);
     } else {
       // Don't bother incrementing the age, just push
       // onto the claimed_stack..
       push_breadth(obj);
     }
     // Save the mark if needed
     PSScavenge::oop_promotion_failed(obj, obj_mark);
   }  else {
     // We lost, someone else "owns" this object
     guarantee(obj->is_forwarded(), "Object must be forwarded if the cas failed.");
     // No unallocation to worry about.
     obj = obj->forwardee();
   }
 #ifdef DEBUG
   if (TraceScavenge) {
     gclog_or_tty->print_cr("{%s %s 0x%x (%d)}",
                            "promotion-failure",
                            obj->blueprint()->internal_name(),
                            obj, obj->size());
   }
 #endif
   return obj;
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp@d1605aabd0a1 (annotated)

src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp